<?php
    header('Content-type:text/html;charset=utf-8');
    $name='小明';
    $score=78;
    if(is_int($score)||is_float($score)){
        if($score>=90&&$score<=100){
            $str='A';
        }elseif($score>=80&&$score<=90){
            $str='B';
        }elseif($score>=70&&$score<=80) {
            $str='C';
        }elseif($score>=60&&$score<=70) {
            $str='D';
        }elseif($score>=0&&$score<=60) {
            $str='E';
        }
    }else{
        $str='输入的学生成绩不是数值';
    }
echo "<h2>学生成绩等级</h2><p>学生姓名:".$name."</p><p>学生分数: ".$score."分</p>成绩等级:".$str;
?>